1. Field of the Invention
The present invention relates to a resin binder for a toner used for developing electrostatic latent images formed in electrophotography, electrostatic recording method, electrostatic printing, and the like, and a toner comprising the resin binder.
2. Discussion of the Related Art
As a means for improving the low-temperature fixing ability, which is one of the major problems to be solved in electrophotography, a resin binder for a toner comprising a crystalline polyester has been proposed (Japanese Patent Laid-Open No. 2001-222138).
However, the low-temperature fixing ability and the pulverizability of a resin generally tend to be properties which conflict with each other. Therefore, in a crystalline polyester, there also arises a problem that the resin is fused to the blades or the wall of a rough pulverizer during rough pulverization. In addition, since a toner comprising a crystalline polyester is fixed at a temperature lower than that of a conventional toner, the toner viscosity during fixing becomes high, so that sheet adhesion around a fixing device such as a fixing roller is likely to be caused. In order to solve this problem, there has been proposed to add a wax to a toner. However, mere addition of a wax cannot excellently improve various properties in a good balance.
An object of the present invention is to provide a resin binder for a toner which is highly excellent in the low-temperature fixing ability, and excellent in prevention of sheet adhesion and storage property, without causing the lowering of pulverizability due to the fusion to a rough pulverizer and the like during rough pulverization; and a toner comprising the resin binder.
These and other objects of the present invention will be apparent from the following description.